Sorry if I'm reviving an old thread, but I just noticed the same issue. I just picked up my 2011 WRX about 3 weeks ago. It has almost 800 miles on it so far. Just today on my way to work I noticed a clicking noise when I press in the clutch. It doesn't happen when I'm letting the clutch out, just when I press it in. It happens at the top also, when I have it pressed in about 1-2 inches. I sit in a lot of traffic going to and from work every day so I'm on and off the clutch a lot. Someone said it could be the throwout bearing, but I wouldn't think it would be worn out in just 800 miles of driving.
Anyone have the same problem or have any ideas what it could be? I'm going to see if the noise continues, and if so then I'm gonna take it to the dealer and have then take a look at it. Hopefully whatever it is, it's covered under warranty.